Postretirement and Other Employee Benefits - Fair Value of Plan Assets (Details) - USD ($) $ in Millions	Aug. 31, 2023	Aug. 31, 2022	Aug. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Fair Value	$ 486	$ 459	$ 576
Asset Allocation	100.00%	100.00%
Cash and cash equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value	$ 17	$ 13
Asset Allocation	3.00%	3.00%
Global equity securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value	$ 213	$ 197
Asset Allocation	44.00%	43.00%
Corporate bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value	$ 216	$ 203
Asset Allocation	45.00%	44.00%
Government bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value	$ 30	$ 34
Asset Allocation	6.00%	7.00%
Insurance contracts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value	$ 10	$ 12
Asset Allocation	2.00%	3.00%